JP2021060035A - Vacuum pump, scroll pump, and method of manufacturing the same - Google Patents

Abstract

To facilitate the usage of a scroll pump in a vacuum system.SOLUTION: A scroll pump 20 is a vacuum pump, and is equipped with a pressure sensor 60 assembled in the scroll pump 20. When the pressure of the scroll pump 20 is too high, a high vacuum pump is switched off and/or an interposed valve is closed or equivalent means can be taken. Then, the high vacuum pump can be certainly protected from operation with excessive high pressure.SELECTED DRAWING: Figure 3

Description

The present application relates to improvements in vacuum pumps, in particular scroll pumps and methods thereof.

A first aspect of the present invention has a movable scroll member that can be eccentrically excited to generate a pumping action, the scroll member having a base plate and a scroll wall extending from the base plate. Start from the scroll pump. One object of the present invention is to facilitate the manufacture of such a scroll pump. This problem is solved, in particular, by providing the base plate with at least two retaining protrusions located on the outside, spaced apart from the circumference of the base plate.

The scroll wall extends from the flat surface of the base plate and thus protrudes axially from the base plate, whereas the retaining protrusion radially protrudes from the circumference of the base plate, i.e., the radial outer edge of the base plate. It is a department.

With these holding protrusions, the scroll member can be easily clamped, especially directly. The holding protrusions are particularly arranged on the circumferential side and / or are uniformly arranged over the circumference.

Advantageously, it can be assumed that at least or exactly three or four retaining protrusions are provided.

The holding protrusions can preferably be configured such that the material dimensions are not expanded by the holding protrusions.

For example, the first intermediate portion of the circumference of the base plate between two adjacent holding protrusions can have a larger radial height than the second intermediate portion. This makes it easy to achieve an increase in mass in the first intermediate portion, which is useful, for example, in correcting imbalances.

Preferably, it can be assumed that the first intermediate portion is located at least roughly opposed to the outermost 120 ° portion and / or the outermost 180 ° portion of the scroll wall. Thereby, the mass of the outermost portion of the scroll wall can be easily compensated by the first intermediate portion.

According to another embodiment, it is assumed that no fixing holes are arranged in the base plate in or near at least one retaining protrusion region. Thereby, the stability of the scroll member can be easily improved. This is because the holding force against the clamping device by the holding protrusion is not weakened by the mounting holes located nearby. The fixing holes in the scroll member can be used, for example, for later mounting of corrugated bellows and / or bearing elements.

The problem of the first aspect is also solved by the method of manufacturing a scroll pump, particularly the scroll pump of the type described above, in which case the scroll pump is a movable scroll that can be eccentrically excited to generate a pumping action. It has a member, and the scroll member is directly clamped to the clamping device with the base plate.

The direct clamp simplifies the method significantly. In particular, there is no need for a clamp aid to be attached to the scroll member.

For example, in a scroll member, a base plate and a scroll wall extending from the base plate are manufactured together by cutting. Preferably, the clamping device can have a claw chuck or can be a claw chuck. Alternatively or additionally, preferably, the claws of the claw chuck of the clamping device can engage at least two holding protrusions located on the outside of the base plate, spaced apart from each other. ..

According to one evolution, the clamping device allows tool access to the scroll member not only from one side of the base plate where the scroll wall is formed, but also from the other side of the base plate, especially the opposite side. As it is, it is supposed to be configured. In this case, preferably, the scroll member can be machined from both sides and / or finished by machining from both sides with at least substantially one clamp.

The clamping device can preferably be or have a claw chuck, particularly a 3-claw chuck or a 4-claw chuck.

The present invention also relates to a clamping device, generally and independently of itself, for particularly directly clamping the scroll member of the scroll pump, particularly with a claw chuck, the scroll device having tool access to the scroll member of the base plate. , It is configured so that it is possible not only from one side where the scroll wall is formed, but also from the other side of the base plate. This could preferably be, for example, a continuously extending void, especially a claw chuck with holes.

A second aspect of the present invention is to have a scroll member, the scroll member having a base plate and a scroll wall extending from the base plate, the scroll wall being on the side of the scroll wall opposite to the base plate. It has a groove at the end, the groove contains a sealing element, and the groove starts from a scroll pump defined by two opposing side walls. One problem is to facilitate the handling of the scroll member when assembling the scroll pump and / or to reduce the risk of damage to the scroll member during handling. The challenge is that, especially in the first scroll portion, the first side wall is thicker than the second side wall in the first scroll portion and / or one or both side walls in the second scroll portion. It is solved by being.

Due to the locally thicker side wall construction, the side walls are reinforced locally, especially in vulnerable areas. Therefore, the risk of damage is reduced and handling is easier.

According to one embodiment, it is assumed that the first scroll portion is the outer edge portion of the scroll wall. The first scroll portion is particularly vulnerable to damage. Further, since the scroll portion located inside is protected by the scroll portion located particularly outside, there is no need to "thicken" the scroll portion inside. Therefore, from the viewpoint of preferably reducing the mass as a whole, preferably, only the outer end portion of the scroll wall has the thickened portion.

In general, the first scroll portion can preferably be placed within the last half of the scroll of the scroll wall, at least roughly. The first scroll portion may be particularly damaged. In this case, it is advantageous that the penultimate half of the winding is also located on the outside in principle, but it is utilized that the larger protrusion of the base plate already has some protection. Therefore, the mass of the scroll member can be kept relatively small.

One evolutionary form assumes that the first scroll portion extends at a minimum of 100 °, preferably at a minimum of 140 °. Preferably, the first scroll portion can optionally or additionally extend over a maximum of 200 °, preferably at a maximum of 180 °. In the areas described, the advantages of the present invention are particularly pronounced.

According to another embodiment, the first scroll portion is arranged in a non-pumping region of the scroll wall. This advantageously utilizes the fact that generally tight manufacturing tolerances are generally less required in regions where such pumping action is not achieved. Therefore, the thickened portion can be manufactured particularly easily.

The first side wall can be a radial outer side wall, according to another advantageous example. This makes it possible to significantly reduce the risk of damage.

Preferably, the first sidewall can be thicker, for example, by a minimum of 0.2 mm and / or by a maximum of 1 mm, in particular by a maximum of 0.7 mm, and in particular by a maximum of 0.4 mm. This allows for particularly good stabilization, especially with relatively small additional mass.

Another embodiment assumes that the scroll member is movable and can be eccentrically excited to generate a pumping action. The advantages of the present invention are particularly noticeable in movable scroll members.

According to a third aspect of the present invention, a vacuum pump, particularly a scroll pump, comprises an electronic housing in which one or more electronic components are arranged. One object of the present invention is to provide good heat dissipation or good cooling from electronic components. This problem is solved, in particular, by providing a separate chamber within the electronics housing for at least one electronics component and enclosing the electronics component in the chamber.

In addition to particularly good heat dissipation, the chamber additionally shields the electronic components, especially against thermal radiation and electromagnetic effects. In addition, a separate chamber allows the use of relatively small amounts of encapsulation material. Encapsulation materials are usually expensive. Preferably, the electronics housing can be made of metal.

The encapsulation material used for encapsulation is particularly configured to be thermally conductive and / or electrically insulating.

For example, a plurality of separate chambers can be provided. One embodiment assumes that a plurality of chambers each contain at least one electronic component. Therefore, in particular, various electronic components can be reliably separated from each other, especially shielded from each other. At the same time, advantageous heat dissipation is possible.

For example, advantageously, it can be envisioned that there is at least one separate chamber in which the electronic components are not enclosed. In general, the electronics housing can be configured identically, for example specifically for various pumps in a series, in which case separate chambers are provided for the various electronics components and the electronics components , Incorporated or not incorporated in the chamber, depending on the pump type. In that respect, at least one separate chamber is advantageously provided, in which the electronic components used in another pump type can be incorporated, particularly encapsulated. Therefore, some kind of modular system can be realized, which makes it possible to realize significant cost advantages in production.

According to a fourth aspect of the invention, it starts with a scroll pump. One challenge is to facilitate the application of scroll pumps in vacuum systems. This challenge is solved, in particular, by having a pressure sensor with a built-in pump.

Vacuum systems often already have a pressure sensor, for example in a vacuum chamber. By incorporating the pressure sensor into the scroll pump, the scroll pump can then be operated sufficiently independently and without the cumbersome connection to the pressure sensor of the vacuum system. Conversely, additional pressure sensors can be omitted in the vacuum system, for example. In general, a built-in pressure sensor monitors the scroll pump itself, allowing it to be done without the hassle of a process guide system. Therefore, the wear condition of the pump in particular can be monitored according to the measured pressure. In particular, when the scroll pump is provided as a fore pump for a high vacuum pump, the built-in pressure sensor can further guarantee an improvement in operational certainty. Thus, for example, when the pressure in the scroll pump is too high, the high vacuum pump can be switched off and / or the intervening valve closed or equivalent measures can be taken. The high vacuum pump can then reliably protect against operating at excessively high pressures.

Preferably, the pressure sensor can be incorporated into the control unit of the scroll pump and / or vacuum system. Thus, the scroll pump and / or vacuum system can be well controlled in a closed or open loop, which can also be controlled based on the known pressure in the scroll pump.

According to one embodiment, a pressure sensor is provided to measure the suction pressure of the pump, or the pressure between the two scroll walls acting as a pump or between the two scroll walls in the scroll portion acting as a pump. Is assumed. Both allow for more precise monitoring of wear on the pump process and pumps, especially on sealing elements such as tip seals or scroll walls.

In another advantageous embodiment, the pressure sensor is screwed into the scroll pump components. This allows for a simple structure of the scroll pump on the one hand and flexible handling on the other hand. Instead of the built-in pressure sensor, for example, a blind plug can simply be provided when the built-in pressure sensor is not essential for the user's process. Nevertheless, in this case, the built-in pressure sensor can be easily retrofitted. The component into which the pressure sensor is screwed can be, for example, a housing element and / or a fixed scroll member. In particular, the pressure sensor can be screwed into a fixed scroll member in the axial direction.

According to one evolution, it can be assumed that the pressure sensor is located in the cooling system of the pump, eg, the cooling airflow of the fan. Therefore, the pressure sensor can be cooled directly in an advantageous manner, which improves the service life and measurement accuracy of the pressure sensor. Preferably, the pressure sensor can be located at least roughly at the beginning of the cooling air flow, i.e. next to the fan and / or in the air guide hood.

In principle, for example, a plurality of pressure sensors incorporated in the scroll pump may be provided. This can further improve control and wear monitoring in particular.

In a fifth aspect of the invention, the scroll pump has an eccentric shaft that eccentrically excites the movable scroll member of the pump, with a plurality of balance weights of various types eccentric, each of which is a particular type of scroll pump. Start with the method of assembling the scroll pump provided for mounting on the shaft. One challenge is to ensure that the assembly is particularly reliable. This challenge specifically addresses the eccentric shaft, balance weights and / or other components of the pump, such as the pump housing, so that only certain types of balance weights can be mounted on the eccentric shaft at a particular mounting position. It is solved by making it.

Therefore, the wrong type of balance weight assembly for the relevant pump can be reliably avoided. Therefore, the assembly becomes more reliable as a whole.

The term "non-assembleable" includes the fact that balance weights can be attached, but subsequent assembly, such as insertion of the shaft into the pump housing, is not entirely possible. Therefore, the assembler finds something wrong because he cannot complete the assembly. This ensures correct assembly, especially by simple means. "Unable to assemble" can further mean that the balance weight cannot be surface-contacted with the eccentric shaft by the contact surface provided on the balance weight. This is because, for example, the contact is hindered by the steps provided on the shaft. Thus, in general, for example, the wrong type of balance weight cannot be brought into perfect contact with the eccentric shaft. In general, for example, an eccentric shaft with the wrong type of balance weight assembled cannot be fully inserted into the pump housing of the pump.

For example, an eccentric shaft and / or another component can be expected to collide with at least the first type of balance weight when attempting assembly. In this case, the first type is the wrong type for the corresponding eccentric shaft.

In some embodiments, the eccentric shaft and / or another component has protrusions and / or steps that collide with at least one first type of balance weight when attempting assembly. This makes it especially easy to prevent incorrect assembly.

In the sixth aspect of the present invention, the pump body is provided, the inside of which defines the pump chamber, and the outside of the pump body, a valve for controlling the supply of ballast gas to the pump chamber is arranged, and the valve is operated. Having a grip, the operating grip is rotatably coupled to the static element of the valve and / or fixedly coupled to the rotatable element of the valve via at least one mounting screw. The mounting screw departs from a vacuum pump, especially a scroll pump, which is screwed into a static element or a rotatable element through a hole provided in the operating grip. One object of the present invention is to extend the service life and / or maintenance interval of the valve and / or at least one component of the valve. This problem is solved, in particular, by providing a lid that closes the hole.

The lid prevents, or at least reduces, the entry of dirt into the holes and ultimately into sensitive areas.

The valve can have, for example, one particularly axially pressed O-ring as a sealing means. When the valve is activated, relative movement is exerted on the O-ring. If dirt, such as particles, reaches the sliding surface of the O-ring, this can lead to premature failure of the O-ring. This is reliably reduced or prevented by the lid.

The pump body can be, for example, a static scroll member and / or a housing member.

The lid can be inserted into the operating grip, for example. For example, the lid can be inserted into the holes mentioned above or into one hole. More generally, for example, the lid can be held in the operating grip, especially in the holes, by a tight fit. For insertion, the lid can have one or more protrusions, eg, in the form of pins.

Further, it can be assumed that the lid is inserted into at least two holes and / or the lid closes at least one hole in which the lid is not inserted.

In another embodiment, the operating grip has a metal base element and at least a plastic portion in a grippable area for manual operation. This results in good corrosion resistance and at the same time low manufacturing costs. In addition, the plastic portion can be kept at a relatively low temperature or can be manipulated well based on the suppressed heat conduction with respect to the metal. The base element can be made of, for example, special steel. The base element can be enclosed in plastic, for example by injection molding. The base element can have, for example, a check valve and / or a connecting thread.

For example, a check valve can be incorporated and arranged in the operation grip. Further, for example, the gas ballast valve can be configured in particular in two stages. Further, for example, the operating grip may be provided with an inlet and / or connection for ballast gas.

A seventh aspect of the invention starts with a vacuum pump, especially a scroll pump, which comprises a fan with controllable speed for cooling the pump. One challenge is to configure the cooling specifically as required and / or reduce the acoustic emissions of the fan. In particular, the vacuum pump comprises a temperature sensor and a control device, and the control device controls the rotation speed of the fan according to the power consumption of the drive device of the pump and the temperature measured by the temperature sensor. It is solved by being configured as.

The measured temperature can preferably be the temperature in the pump, eg, the pump components and / or the space within the pump, eg, the suction chamber or the pump chamber. In one embodiment, control is assumed to be in response to the temperature of the pump motor, motor windings, drive electronics or power electronics, pump body and / or housing as measured by a temperature sensor. In principle, these temperature values can be measured by, for example, a plurality of temperature sensors, or, in general, a plurality of temperature sensors can be provided.

According to one embodiment, a first threshold of temperature is set and control is performed only when the measured temperature is above the first threshold and / or below the first threshold. It is assumed that the fan speed is kept constant at zero or at the minimum speed. This allows the fan to retain a small amount of acoustic emission when the cooling requirements are low, that is, when the measured temperature is low. In addition, this allows the pump to quickly heat up to the desired operating temperature after being switched on. This is advantageous, for example, because the degree of clearance between scrolls depends on the thermal expansion of the components and is therefore optimized only within the framework of a particular operating temperature range. Therefore, this embodiment makes it possible to quickly achieve favorable pump performance. In addition, a rapid rise in temperature achieves improved compatibility with the condensing medium.

The first threshold can preferably be a minimum of 40 ° C. and / or a maximum of 60 ° C., particularly about 50 ° C. The minimum number of revolutions is generally lower than the maximum number of revolutions, especially much lower, especially less than 30%, especially less than 20%, especially less than 10% of the maximum number of revolutions.

According to another embodiment, when a second threshold of temperature is set and the measured temperature exceeds the second threshold, the fan speed is kept constant at the maximum speed. This easily ensures that maximum cooling capacity is achieved at high temperatures. Therefore, cooling can be easily performed as required. In general, embodiments with a second threshold are independent of embodiments with a first threshold and vice versa. Moreover, these can be combined advantageously. In that respect, the term "second" threshold has only been chosen for ease of reference, and the "first" threshold does not need to be further set.

When a plurality of temperature sensors are provided, the above-mentioned threshold values may be different for each of the plurality of temperature sensors, for example.

The control device can be configured to reduce the drive output of the pump, for example, in response to the temperature of the vacuum pump as measured by the temperature sensor. This feature can also be referred to as "derating". For example, it can be assumed that the fan is adjusted to maximum speed when the derating conditions are met and / or when the pump is in the derating state, i.e. when the drive output is reduced.

The rotation speed of the fan can preferably be controlled by pulse width modulation (PWM).

The maximum fan speed may be adaptable, for example. Therefore, for example, it may be advantageous to reduce the maximum fan speed in order to improve steam compatibility.

An eighth aspect of the invention starts with a vacuum pump, preferably a scroll pump, comprising an electrically driven fan and an air guide hood. One object of the present invention is to reliably establish an electrical connection of a fan to a supply connection, particularly reliably, especially over a long period of time. The challenge is, in particular, the conductor, preferably the cable, from the fan, preferably by an air hood guide, to the supply connection for the fan, and the conductor, preferably a detachable electrical connector, preferably. Is connected to the supply connection via a plug and the connector is resolved by being separated from the air flow path defined by the air guide hood by a partition wall. Preferably, the connector can be located in the air guide hood, at least in part. The partition wall can be integrally coupled with, for example, an air guide hood.

Ambient air, which may contain dirt and dust, is sucked in through the fan and guided along a predetermined air flow path. The partition wall does not prevent inhaled impurities or dust from entering the connector, especially as a result, into the electronic housing of the pump. Rather, the partition wall only allows the inhaled air to be guided by the side of the connector at intervals.

The fan can preferably be mounted specifically on the air guide hood, especially on the air guide hood. The connector can be preferably configured to be detachable.

In one embodiment, it can be assumed that a conductor, in particular a cable, is guided from the connector through a recess provided in the partition wall. Therefore, the conductor can be easily guided from the connector to the fan. The recess can be, for example, a notch that can preferably be formed in a V shape.

Another embodiment assumes that the recesses are arranged offset in the circumferential direction with respect to the connector. This extends the path from the recess to the connector, allowing impurities passing through the recess to travel a longer distance to the connector, thus reducing the probability of impurities reaching the connector. .. As a result, the labyrinth effect is easily realized.

In a ninth aspect of the invention, the scrolling member comprises a fixed scrolling member during operation, the fixed scrolling member starting from the scrolling pump, which is detachably coupled to the housing element of the pump. One object of the present invention is to facilitate the removal of the scroll member from the housing element. The challenge is, in particular, that the scroll member and / or the housing element is provided with at least one pulling thread for removing the scroll member from the housing element, preferably on opposite sides in the radial direction. This is solved by providing two pull-off threads arranged in.

The pull-off thread allows the scroll member to be easily and in a predetermined shape to pull away from the housing element and thus be removed.

In general, preferably, there is no through hole associated with the pulling thread provided in each of the other constituent members so as to be aligned in the axial direction. Rather, preferably, the pulling thread can be abutted by, or associated with, a flat surface or recess of another component.

In general, a plurality of, in particular at least two, pull-off threads may be provided, which are preferably capable of being evenly distributed over the circumference and / or radially opposite. Can be placed on the side. As a result, the scroll member can be removed particularly uniformly. Therefore, for example, if there is no pulling thread, it is possible to avoid the inclination that may occur when removing the scroll member that abuts on the housing element at the intermediate fitting portion. In some cases, the existing sealing means may tilt or lock. In particular, a plurality of pulling threads can avoid or at least reduce these problems of non-uniform load.

According to another embodiment, the scroll member and / or the component adjacent to the housing element may collide with the screw head of the release screw screwed into the release thread in some cases, so that the component Is configured so that it cannot be fully assembled. As a result, incorrect assembly can be easily avoided. This is because it is guaranteed that no screw, for example, which can prevent the scroll member from properly contacting the housing element, is screwed into the pull-off thread. This component can be, in particular, an air guide hood. For collision with the screw head, for example, protrusions and / or domes can be provided.

Of course, not only the individual viewpoints of the present invention, but also the viewpoints described below based on the drawings can be combined in an advantageous manner.

The present invention will be described below with reference to merely exemplary schematics.

The scroll pump is shown in sectional view. The electronic housing of the scroll pump is shown. The scroll pump is shown in perspective view and the selected elements are exposed. Shows the pressure sensor built into the pump. The movable scroll member of the pump is shown. FIG. 5 shows a scroll member on another side opposite to the visible side. The clamp device for the scroll member is shown. An eccentric shaft with different scroll pump balance weights is shown. An eccentric shaft with different scroll pump balance weights is shown. A gas ballast valve having an operating grip is shown in a perspective view. The valve of FIG. 10 is shown in cross section. The partial areas of the scroll members of FIGS. 5 and 6 are shown. A cross-sectional view of a scroll member passing through a scroll wall in the outer edge region is shown. The air guide hood of the scroll pump of FIG. 1 is shown in a perspective view. The pull-off thread is shown in cross-sectional view.

FIG. 1 shows a vacuum pump configured as a scroll pump 20. The vacuum pump has a first housing element 22 and a second housing element 24, in which case the second housing element 24 has a pumping structure, i.e., a scroll wall 26. Therefore, the second housing element 24 forms a fixed scroll member of the scroll pump 20. The scroll wall 26 interacts with the scroll wall 28 of the movable scroll member 30, in which case the movable scroll member 30 is eccentrically excited via the eccentric shaft 32 to generate a pumping action. In this case, the gas to be pumped is pumped from the inlet 31 defined in the first housing element 22 to the outlet 33 defined in the second housing element 24.

The eccentric shaft 32 is driven by a motor 34 and is pivotally supported by two rolling bearings 36. The eccentric shaft 32 has an eccentric journal 38 arranged eccentrically with respect to the rotation axis of the eccentric shaft 32, and the eccentric journal 38 eccentric swing of the eccentric journal 38 via another rolling bearing 40. Is transmitted to the movable scroll member 30. The movable scroll member 30 is further attached to the left end of the corrugated bellows 42 in FIG. 1 for sealing purposes, the right end of which is attached to the first housing element 22. ing. The left end of the corrugated bellows 42 follows the swing of the movable scroll member 30.

The scroll pump 20 has a fan 44 for generating a cooling air flow. An air guide hood 46 is provided for this cooling air flow. A fan 44 is also attached to the air guide hood 46. The air guide hood 46 and housing elements 22, 24 are molded so that the cooling air flow generally flows around the entire pump housing and thus good cooling performance is achieved.

The scroll pump 20 further has an electronics housing 48, in which a control device and a power electronics component for driving the motor 34 are arranged. The electronics housing 48 further forms a stand leg for the pump 20. The passage 50 is visible between the electronics housing 48 and the first housing element 22. Both are effectively cooled as the airflow generated by the fan 44 through the passage 50 is guided along the first housing element 22 and also along the electronics housing 48.

The electronics housing 48 is specifically shown in detail in FIG. The electronics housing 48 has a plurality of separate chambers 52. In these chambers 52, electronic components can be encapsulated and thus advantageously shielded. Preferably, when encapsulating the electronic component, the encapsulation material used can be as small as possible. For example, the encapsulant material can be introduced first into the chamber 52, followed by the electronic components. Preferably, the chamber 52 can be configured such that various forms of electronic components, in particular various forms of mounting, can be placed and / or encapsulated within the electronics housing 48. .. In this case, in certain embodiments, the individual chambers 52 can also be left empty, i.e., they do not have to have electronic components. Therefore, so-called modular systems can be easily implemented for various pump types. The encapsulation material can be configured to be particularly thermally conductive and / or electrically insulating.

A plurality of walls or fins 54 are formed on the rear side of the electronics housing 48 with respect to FIG. 2, and the walls or fins 54 define a plurality of passages 50 for guiding a cooling air flow. The chamber 52 further allows particularly good heat dissipation from the electronic components located within the chamber 52 to the fins 54, especially in combination with the thermally conductive encapsulating material. Therefore, the electronic component can be cooled particularly effectively and its useful life is improved.

Although the entire scroll pump 20 is shown in a perspective view in FIG. 3, in FIG. 3, since the air guide hood 46 is omitted, the fixed scroll member 24 and the fan 44 are particularly visible. The fixed scroll member 24 is provided with a plurality of recesses 56 arranged radially, and the recesses 56 define fins 58 arranged between the recesses 56, respectively. The cooling air flow generated by the fan 44 is guided through the recess 56 and by the fins 58, thus cooling the fixed scroll member 24 particularly effectively. At that time, the cooling air flow first flows around the fixed scroll member 24, and then finally flows around the first housing element 22 or the electronic housing 48. This arrangement is particularly advantageous because the pumping region of the pump 20 has a high calorific value based on compression during operation and is therefore preferentially cooled there.

The pump 20 has a pressure sensor 60 built into the pump 20. The pressure sensor 60 is arranged in the air guide hood 46 and is screwed into the fixed scroll member 24. The pressure sensor 60 is connected to the electronics housing 48 and a control device located therein via a cable connection that is only partially shown. In this case, the pressure sensor 60 is incorporated in the control unit of the scroll pump 20. For example, the motor 34 visible in FIG. 1 can be controlled according to the pressure measured by the pressure sensor 60. For example, if the pump 20 is used in a vacuum system as a forepump for a high vacuum pump, for example, the high vacuum pump can only be turned on when the pressure sensor 60 measures a sufficiently low pressure. Therefore, the high vacuum pump can be protected from damage.

FIG. 4 shows a cross-sectional view of the pressure sensor 60 and the arrangement of the pressure sensor 60 on the fixed scroll member 24. A passage 62 is provided for the pressure sensor 60, where the passage 62 is an outer region that does not pump between the scroll wall 26 of the fixed scroll member 24 and the scroll wall 28 of the movable scroll member 30. Open to. Therefore, the pressure sensor measures the suction pressure of the pump. Alternatively or additionally, for example, the pressure between the scroll wall 26 and the scroll wall 28 can be measured in the pumping region. Therefore, for example, an intermediate pressure can be measured according to the position of the pressure sensor 60 or the passage 62.

The pressure sensor 60 makes it possible to recognize the wear state of the pumping component, in particular the seal element 64, also referred to as the tip seal, with respect to the identification of compression, for example. In addition, the measured suction pressure can also be used to control the pump (particularly the pump speed). Therefore, for example, the suction pressure can be adjusted by presetting the suction pressure on the software side and changing the pump rotation speed. Depending on the measured pressure, it is also conceivable to compensate for the pressure increase due to wear by increasing the number of revolutions. Therefore, the replacement of the chip seal can be postponed or a longer replacement interval can be achieved. Therefore, the data of the pressure sensor 60 can be generally used for, for example, wear identification, pump control according to the situation, process control, and the like.

The pressure sensor 60 can be optionally provided, for example. Instead of the pressure sensor 60, for example, a blind plug for closing the passage 62 can be provided. In this case, the pressure sensor 60 can be retrofitted, for example, if necessary. Especially with respect to retrofitting, and generally advantageously, it can be assumed that the pressure sensor 60 is automatically recognized as being connected to the control device of the pump 20.

The pressure sensor 60 is arranged in the cooling air flow of the fan 44. As a result, the pressure sensor 60 is also advantageously cooled. As a result, no special measures need to be taken to increase the heat resistance of the pressure sensor 60, and thus a low cost sensor can be used.

Further, the pressure sensor 60 is arranged so that the outer dimensions of the pump 20 are not enlarged by the pressure sensor 60, and therefore the pump 20 is kept compact.

5 and 6 show the movable scroll member 30 in different observation directions. In FIG. 5, the spiral structure of the scroll wall 28 is particularly well visible. In addition to the scroll wall 28, the scroll member 30 has a base plate 66, from which the scroll wall 28 extends.

In FIG. 6, the side of the base plate 66 opposite to the scroll wall 28 is visible. On this side, the base plate has, among other things, a plurality of mounting voids for mounting the bearing 40 and corrugated bellows 42 visible in FIG. 1, for example.

On the outside of the base plate 66, there are three retaining protrusions 68 spaced around the circumference of the base plate 66 and evenly distributed over the circumference. In this case, the holding protrusion 68 extends outward in the radial direction. The holding protrusions 68, in particular, all have the same radial height.

A first intermediate portion 70 around the circumference of the base plate 66 extends between the two holding protrusions 68. The first intermediate portion 70 has a larger radial height than the second intermediate portion 72 and the third intermediate portion 74. The first intermediate portion 70 is arranged to face the outermost 120 ° portion of the scroll wall 28.

When making the movable scroll member 30, preferably the base plate 66 and the scroll wall 28 are made by cutting together from one solid material, that is, the scroll wall 28 and the base plate 66 are integrally formed. ing.

For example, during finishing, the scroll member 30 can be directly clamped by the holding protrusion 68. Within the same single clamp range, for example, the side of the base plate 66 shown in FIG. 6 can also be machined, especially the mounting vacancy. In principle, within the range of this clamp, the scroll wall 28 can be made by cutting from the material of the solid material.

For this purpose, the scroll member 30 can be clamped using, for example, a clamping device 76, as shown in FIG. The clamp device 76 has a hydraulic three-claw chuck 78 for directly contacting the three holding protrusions 68. Further, the clamp device 76 has a vacant space 80 that penetrates, and the vacant space 80 enables tool access to the scroll member 30, particularly to the side of the scroll member 30 as shown in FIG. Therefore, it is possible to perform a plurality of processing operations from both sides during the clamping, particularly at least one finishing processing of the scroll wall 28 and processing of a mounting space.

The contour of the holding protrusion 68 and the clamping pressure of the clamping device 76 are preferably selected so that the scroll member 30 is not critically deformed. The three holding protrusions 68 are preferably selected so that the outer dimensions, that is, the maximum diameter of the scroll member 30, are not enlarged. Therefore, it is possible to save material on the one hand and cutting amount on the other hand. The retaining protrusion 68 is specifically configured to provide access to the threaded fastening of the corrugated bellows 42 and / or is located at such an angular position. The number of screw fastening points of the corrugated bellows 42 is preferably not the same as the number of holding protrusions 68 in the movable scroll member 30.

Two balance weights 82 are attached to the eccentric shaft 32 of FIG. 1 to compensate for the imbalance of the excited system. FIG. 8 shows an enlarged area of the balance weight 82 on the right side in FIG. The balance weight 82 is screwed to the eccentric shaft 32.

FIG. 9 preferably shows a similar partial view of another scroll pump belonging to the same series as the pump 20 of FIG. The pump according to FIG. 9 has other dimensions in particular and therefore requires a different balance weight 82.

The eccentric shaft 32, the balance weight 82 and the housing element 22 can be assembled to the eccentric shaft 32 at the mounting positions shown respectively, and only one specific type of the two types of the balance weight 82 shown can be assembled to the eccentric shaft 32. It is sized so that it is.

The balance weight 82 is dimensioned with specific dimensions of the structural space set for the balance weight 82 in FIGS. 8 and 9, whereby the balance weight 82 of FIG. 9 is assembled to the eccentric shaft 32. It is clear that it is impossible to attach and vice versa. Of course, the dimensions entered are merely exemplary.

Therefore, in FIG. 8, the distance between the mounting hole 84 and the shaft step portion 86 is 9.7 mm. The balance weight 82 of FIG. 8 is formed to be shorter in the corresponding direction, that is, to a length of 9 mm, and therefore can be assembled without any problem. Each of the balance weights 82 in FIG. 9 has an extended length of 11 mm as measured from the mounting holes. Therefore, the balance weight 82 of FIG. 9 cannot be assembled to the eccentric shaft 32 of FIG. This is because the shaft step 86 collides with the balance weight 82 when attempting to assemble, or therefore the balance weight 82 of FIG. 9 may be in complete contact with the eccentric shaft 82 of FIG. Because it cannot be done. The balance weight 82 of FIG. 9 is prevented from being assembled in the opposite direction because both of the dimensioned dimensions are larger than the distance between the mounting hole 84 of FIG. 8 and the shaft step portion 86. In addition, the 21.3 mm dimension of the balance weight 82 in FIG. 8 prevents the orientation of the normally correct balance weight 82 in the opposite direction and thus in the wrong assembly.

In FIG. 9, the longitudinal distance between the mounting hole 84 and the housing shoulder 88 is 17.5 mm. The balance weight 82 of FIG. 8, which has an extension of 21.3 mm, should collide with the housing shoulder 88 when the eccentric shaft 32 of FIG. 9 is inserted, so that complete assembly is not possible. Wrong assembly is possible for the time being, but it is definitely recognized. When the balance weight 82 of FIG. 8 is assembled to the eccentric shaft 32 of FIG. 9 by rotating it around the axis of the mounting hole 84, the 21.3 mm extending portion is only a distance of 13.7 mm from the mounting hole 84. It should collide with the shaft shoulders 86 located apart.

The balance weight 82, particularly the balance weight 82 on the motor side, is generally configured to avoid mistaking the balance weight for a balance weight having another structural size during assembly and / or maintenance. The balance weight is preferably attached using a through screw. Similar balance weights of various pump sizes are incorrect balance weights, especially based on adjacent steps on the shaft, the position of the thread and through holes in the balance weights, and the position of the steps in the housing. It is configured to prevent assembly.

10 and 11 show the gas ballast valve 90 of the scroll pump 20. The gas ballast valve 90 is also visible in the overall view of the pump 20 in FIG. 3, and is arranged on the fixed scroll member 24.

The gas ballast valve 90 has an operating grip 92. The operating grip 92 has a plastic body 94 and a base element 96, which is preferably made of special steel. The base element 96 has a through hole 98, which, on the one hand, is provided to connect and introduce ballast gas and, on the other hand, surrounds the check valve 100. The hole 98 is further closed by a plug 102 in the drawing. Instead of the plug 102, for example, a filter can be provided, in which case the ballast gas may be preferably air and enters the valve 90 particularly directly through the filter.

The operating grip 92 is attached to the rotatable element 106 of the valve 90 by three mounting screws 104. The mounting screws 104 are arranged in the respective holes 108 and only one of them is visible in the selected cross-sectional view of FIG. The rotatable element 106 is rotatably attached to the second housing element 24 by a mounting screw (not shown) extending through the hole 110.

To operate the valve 90, a rotational moment manually applied to the operating grip 92 is transmitted to the rotatable element 106, thus rotating the rotatable element 106. As a result, the hole 98 communicates with the inside of the housing. In this case, the valve 90 is provided with three switching positions, that is, the switching position which is the shutoff position shown in FIG. 10, and the position rotated to the right and the position to be rotated to the left, respectively. In this position, which is rotated left and right, the holes 98 communicate with different regions inside the housing.

The holes 108 and 110 are closed by the lid 112. The sealing action of the gas ballast valve 90 is due to the axially pressed O-ring. When the valve 90 is operated, relative movement is exerted on the O-ring. For example, if dirt such as particles reaches the surface of the O-ring, there is a risk of early failure. The lid 112 prevents dirt and the like from entering the screws of the grip 92.

The lid 112 is attached via a tight fit of three centering elements. Specifically, the lid 112 has an insertion pin (not shown) in each hole 108, and the lid 112 is held in the hole 108 by the insertion pin. Therefore, the holes 108, 110 and the mounting screws arranged therein are protected from dirt. In particular, mounting screws (not shown) located in the holes 110 that allow rotational movement can effectively minimize the entry of dirt into the valve mechanism, thus reducing the useful life of the valve. Can be improved.

The plastic grip, which is injection molded around the base of the special steel, provides good corrosion resistance and at the same time low manufacturing cost. In addition, the reduced thermal conductivity keeps the grip plastic at a low temperature, which allows it to operate well.

The fan 44 is preferably provided with a rotation speed control unit so that it can be visually recognized in FIGS. 1 and 3, for example. The fan is controlled by PWM, for example, according to the power consumption and temperature of the power module housed in the electronics housing 48. The rotation speed is adjusted according to the power consumption. However, control is only possible from a module temperature of 50 ° C. When the pump is in the temperature range of possible derating (temperature-induced decrease in power), the maximum fan speed is automatically controlled. This control achieves a minimum noise level for cold pumps, low noise levels (corresponding to pump noise) at final pressure or low load, and optimal cooling of the pump at the same time as low noise levels. , It becomes possible to secure the maximum cooling output before the output decrease due to the temperature.

The maximum fan speed may be adaptable, especially depending on the situation. For example, reducing the maximum fan speed can be effective for high water vapor compatibility.

FIG. 12 shows the movable scroll member 30 partially and enlarged compared to FIG. A cross-sectional view of the scroll member 30 along line A: A shown in FIG. 12 is shown schematically in FIG. 13, although not at scale.

The scroll wall 28 is on the opposite side of the base plate 66, and at the end of the fixed scroll member 24, which is not shown here, towards the base plate, a seal element 64, the so-called so-called, which is also not shown here. It has a groove 114 for inserting a tip seal. The arrangement in the operating state is well visible in FIG. 4, for example.

The groove 114 is defined by two opposing side walls, namely the inner side wall 116 and the outer side wall 118, on the outside and inside. In the first scroll portion 120, the outer side wall 118 is configured to be thicker than the inner side wall 116 in the first scroll portion 120, and from both side walls 116, 118 in another second scroll portion 122. Is also thickly constructed.

The first scroll portion 120 extends from the location shown in FIG. 12 to the outer edge of the scroll wall 28, for example, as shown in FIG. The first scroll portion 120 extends here, for example, over 163 °.

The first scroll portion 120 forms the outer end portion of the scroll wall 28. In this case, the first scroll portion 120 is, at least partially, particularly completely located in the non-pumping region of the scroll wall 28. In particular, the first scroll portion 120 can at least almost completely occupy the non-pumping region of the scroll wall 28.

As is visible in FIG. 5, preferably, the first intermediate portion 70, which has a larger radial height than the other intermediate portions 72, 74, is located between the two holding protrusions 68. It can be arranged so as to face the scroll portion 120 of 1. Therefore, the imbalance caused by the thicker side wall 118 can be compensated for by the heavier weight of the first intermediate portion 70.

In order to reduce the system load of bearings and other components, the movable scroll member should generally preferably have a small self-weight. Therefore, scroll walls are generally constructed very thin. In addition, the thinner the wall, the smaller the pump size (effective outer diameter). Therefore, the side wall of the tip seal groove is particularly thin. The ratio of the tip seal wall thickness to the total scroll wall thickness is, for example, 0.17 at the maximum. However, based on the tip seal groove, the tip of the scroll wall is extremely sensitive to collisions during handling, such as when assembling or replacing the tip seal. For example, even during transportation, the side wall of the groove can be pressed inward by a slight collision, so that the tip seal can no longer be assembled. To solve this problem, the groove has an asymmetric wall thickness, especially the outward local thickness of the scroll wall. This region preferably does not pump and can therefore be made with greater tolerance. Damage is significantly reduced, especially with one-sided thickening in the last half of the roll. At the rest of the components, preferably no thickening of the scroll wall is required. This is because the walls are protected by the protruding elements of the components.

The air guide hood 46 shown in FIG. 1 defines the air flow, as suggested by the dashed arrow 124. The fan 44 is connected to a control device provided in the electrohousing 48 via a cable (not shown) extending through the air guide hood 46 and a plug-in connection. The plug-in connection has a socket 126 and a plug 128. The socket 126 is mounted on a substrate that is supported by and / or is located within the electronics housing 48. The socket 126 is also visible, for example, in FIGS. 2 and 3. The plug 128 is connected to the fan 44 via a cable (not shown).

The plug-in connection portions 126 and 128 are separated from the air flow 124 by the partition wall 130. The air stream 124 may contain, for example, dust or similar dirt and is therefore isolated from the plug connections 126,128. Thus, on the one hand, the plug-in connections 126,128 themselves are protected, and on the other hand, dirt enters the electronics housing 48 through the openings in the electronics housing 48 provided for the socket 126. It is blocked from reaching the controller and / or power electronics.

In FIG. 14, the air guide hood 46 is individually shown in a perspective view. In particular, the partition wall 130 is visible along with the space provided for the plug 128, defined behind the partition wall 130. The partition wall 130 has a recess 132, here configured as a V-shaped notch, for conducting the cable from the plug 128 to the fan 44.

For example, for cost reduction, a low cost plug-in connector without a seal (eg, without an IP protection code) can be used. This is because the partition wall 130 prevents the sucked air from reaching the electronics through the penetrations of the plug connectors 126,128. The fan cable is laterally guided through the divider 130 by a V-shaped notch 132. The notch 132 has a lateral offset with respect to the plug-in connectors 126,128, thereby achieving a labyrinth effect and thus a further reduction in cooling air leakage to the plug-in connectors 126,128. To. The partition wall 130 in the air guide 46 further improves the air guide into the passage 50 between the electronics housing 48 and the pump housing 22. Only a relatively small amount of fan 44 turbulence and back pressure occur.

FIG. 15 is a schematic cross-sectional view of the contact area between the first housing element 22 and the second housing element or the fixed scroll member 24. The second housing element 24 is partially inserted into the first housing element 22 with an intermediate fit portion 134. In this case, a seal using an O-ring 136 is provided. The intermediate fit 134 also serves, for example, to center the second housing element 24 with respect to the first housing element 22.

For maintenance purposes, for example, to replace the seal element 64, the second housing element 24 must be removed, for example. At that time, when the second housing element 24 is not pulled out straight enough, the intermediate fitting portion 134 or the O-ring 136 may be pinched. In order to solve this problem, a pull-off thread 138 is provided. Preferably, a second pull-off thread located at least on the opposite side in the substantially radial direction can be provided. To guide and remove the second housing element 24 as straight as possible, pull the screw apart until the screw protrudes out of the pull-off thread 138 and abuts on the first housing element 22. Can be screwed into the ridge 138. Further screwing separates the housing elements 22, 24 from each other.

For pulling apart, for example, as shown in FIGS. 1 and 3, mounting screws 142 provided for attaching the second housing element 24 to the first housing element 22 can be used, for example. For this purpose, the pull-off thread 138 preferably has the same thread type as the mounting thread provided for the mounting screw 142.

The second housing element 22 is provided with a recess 140 associated with a pull-off thread 138. If the wear particles are carried as the screw is screwed into the pull thread 138, the wear particles collect in the recess 140. Thus, this type of wear particles is prevented from interfering with, for example, perfect contact between the housing elements 22, 24.

When assembling the fixed scroll member 24, the screws must be unscrewed again. This is because otherwise the complete screw fastening of the fixed scroll member 24 at the first housing element 22 (correct fitting on the plane of the housing) may be prevented. As a result, leaks, tilted postures and poor pump performance can occur. To avoid this assembly error, the air guide vane 46 has at least one dome 144, particularly additional, as shown in FIG. 14, which dome 144 is a screw used to pull apart, especially the mounting. The air guide vanes 46 can be assembled only when the screws 142 are removed again. The air guide hood 46 having the dome 144 is configured so that it can collide with the screw head of the release screw, which is optionally screwed into the release thread 138, so that the air guide hood 46 is complete. It is not possible to assemble to. In particular, the air guide hood 46 can be assembled only when the pulling screw is completely removed.

20 Scroll pump 22 1st housing element 24 2nd housing element / fixed scroll member 26 Scroll wall 28 Scroll wall 30 Movable scroll member 32 Eccentric shaft 34 Motor 36 Rolling bearing 38 Eccentric pin 40 Rolling bearing 42 Wave bellows 44 Fan 46 Air guide hood 48 Electronics housing 50 Passage 52 Chamber 54 Fin 56 Recess 58 Fin 60 Pressure sensor 62 Passage 64 Sealing element 66 Base plate 68 Holding protrusion 70 First intermediate part 72 Second intermediate part 74 Third intermediate part 76 Clamping device 78 3 Claw chuck 80 Vacancy 82 Balance weight 84 Mounting hole 86 Shaft step 88 Housing shoulder 90 Gas ballast valve 92 Operating grip 94 Plastic body 96 Base element 98 hole 100 Check valve 102 Plug 104 Mounting screw 106 Rotation Possible elements 108 holes 110 holes 112 lids 114 grooves 116 inner side walls 118 outer side walls 120 first scroll part 122 second scroll part 124 airflow 126 socket 128 plug 130 partition wall 132 recess 134 intermediate fit 136 O Ring 138 Pull-off screw thread 140 Indentation 142 Mounting screw 144 Dome

Claims (16)

A vacuum pump, the scroll pump (20), comprising a pressure sensor (60) built into the scroll pump (20). The scroll pump (20) according to claim 1, wherein the pressure sensor (60) is connected to the scroll pump (20) and / or the control unit of the vacuum system. The pressure sensor (60) is arranged to measure the suction pressure of the scroll pump (20) or the pressure between two pumping scroll walls (26, 28), claim 1 or 2. Described scroll pump. The scroll pump (20) according to claim 1, wherein the pressure sensor (60) is screwed into a component (24) of the scroll pump (20). The scroll pump according to any one of claims 1 to 4, wherein the pressure sensor (60) is arranged in the cooling air flow of the cooling device (44) of the scroll pump (20). In a vacuum pump (20), especially a scroll pump
A fan (44) with controllable rotation speed for cooling the vacuum pump (20),
With the temperature sensor
A control device configured to control the rotation speed of the fan (44) according to the power consumption of the drive device of the vacuum pump (20) and the temperature measured by the temperature sensor.
A vacuum pump (20). 6 The control is performed according to the temperature of the motor (34), motor windings, drive electronics, pump body and / or housing (22, 24) of the vacuum pump (20) as measured by the temperature sensor. The vacuum pump described in. A first threshold of temperature is set and control is performed only when the measured temperature is above the first threshold and / or below the first threshold, the number of revolutions of the fan (44). The vacuum pump (20) according to claim 6 or 7, wherein is held constant at zero or at a minimum speed. A second threshold of temperature is set, and when the measured temperature exceeds the second threshold, the fan speed is kept constant at the maximum speed, any one of claims 6-8. The vacuum pump (20) according to the above. In a vacuum pump (20), preferably a scroll pump
It comprises an electrically driven fan (44) and an air guide hood (46), a conductor leads from the fan (44) to a supply connection (128) for the fan (44), and the conductor is electrically driven. The connector (126) is connected to the supply connection portion (128) via the connector (126), and the connector (126) is defined by the partition wall (130) and the air flow path (124) by the air guide hood (46). Vacuum pump (20), isolated from. The vacuum pump (20) according to claim 10, wherein the conductor is a cable. The vacuum pump (20) according to claim 10 or 11, wherein the conductor leads from the fan (44) through the air guide hood (46) to the supply connection (128). The vacuum pump (20) according to at least one of claims 10 to 12, wherein the electrical connector (126) is a plug. The vacuum pump (20) according to any one of claims 10 to 13, wherein the connector (126) is at least partially located in the air guide hood (46). The vacuum pump (20) according to any one of claims 10 to 14, wherein the conductor is guided from the connector (126) through a recess (132) provided in the partition wall (130). The vacuum pump (20) according to claim 15, wherein the recess (132) is arranged so as to be displaced in the circumferential direction with respect to the connector (126).

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